Gas powered turbines include a compressor section that draws air in and compresses the air. The compressed air is provided to a combustor along a fluid flowpath. In the combustor, the compressed air is mixed with a fuel and combusted. The resultant gasses from the combustion are expelled across a turbine section along the fluid flowpath. The expansion of the resultant gasses across the turbine section drives the turbine section to rotate. The turbine section is connected to the compressor via a shaft, and rotation of the turbine section drives rotation of the compressor section. In some examples, such as a direct drive turbofan, or a geared turbofan engine, the shaft is further coupled to a fan fore of the compressor and drives the fan to rotate.
Air flows through the flowpath connecting each of the compressor section, the combustor section, and the turbine section. Alternative gas powered turbines, such as marine based turbines, function similarly without the utilization of outside air, and include an analogous flowpath.
Multiple static flowpath elements, such as foil shaped vanes, extend into and through the flowpath. In order to prevent the fluid in the flowpath from escaping through axial joints in the flowpath element assemblies, and thereby escape the flowpath, rope seals are typically employed along at least some of the axial joints.
Due to the nature of gas powered turbines, the gasses passing through the flowpath in the turbine section are at extreme temperatures, and can be elevated from ambient temperatures to extreme temperatures, and vice versa, when the engine is initially starting up and when the engine is winding down. The extreme temperature changes result in expansion and contraction of the flowpath element assemblies. As a result of the expansion and contraction, rope seals can be dislodged or lost, resulting in significant efficiency reductions to the gas powered turbine.